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Hi all, just for your records, attached is a VNWA plot of the NanoVNA RX input impedance. 73, Norbert, DG1KPN

if nothing there in your firmware (no info in boot logo or no version menu) try simply "version" or "info" via serial terminal. But honstly, who cares? just download the latest version and enjoy

Hello, Allow us, please, to we report that in order to be adequately prepared to estimate the uncertainty in NanoVNA measurements using complex differential error regions and real differential error

The FFT assumes that you have a perfect fit of the (co)sinus in the sample range. At higher frequencies the 5kHz start to deviate so the samples may no longer fit perfectly in the fft and you may get

Ok, looked at the source code and it seems that 2mA is used in fundamental mode and 8mA for harmonic (above 300MHz). This should make a big difference in Si5351 output impedance, isn't it? The

What is the Si5351 drive strength being set? 2mA? Is it being increased at >300MHz harmonic bands? It's output impedance may not be 50ohm, and it could be even changing depending on the band. Also

I've been continuing my investigation into improving the nanovna's dynamic range above 900MHz, and have some further results to share. Theory tells us that dynamic range can be improved by increasing

yes, you're wrong with these assumptions. First, voltage suppressor diodes have about 10-15 pF. It works like low-pass filter with cut-off at about 400 MHz. VNA can compensate it by calibration, but

Here are a few comments about diodes and ESD issues for your consideration. I agree that limiter diodes will cause issues; however, the devices I suggested above are not typical limiter diodes.

It is possible. For example 145 MHz antenna has near field range about 1 meter. So, you can place two antennas for example 4 meters away from each other. Signal loss at 4 meters for 145 MHz will be 28

On Fri, 20 Sep 2019 at 18:33, Ken Buscho <kb6kob@...> wrote: > Hi, Folks, > My whole NanoVNA process started because I went out on eBay looking for an > antenna analyzer for ham VHF/UHF use and

I assume this is the firmware changing what is output depending on what mode is selected on the device. If there's a command to reset it, I guess I could do that, but it didn't exist when I made the

academic who might favor that approach, does not have dirt under the finger nails. The hard fact is that in Big City; saturated as it is by truly stupendous microvolt per meter levels from a.m.

I think a torque wrench on a nanoVNA is overkill. The ringing I observed was well above the maximum frequency range. The issue is getting *consistent* connections. Any time you change the sweep

This is a fantastic idea Ken. Just get your "reference" receive antenna as far away as you can and preferably in an open space. Make sure you are not picking up stray radiation from the CH0 "transmit"

get a feel for what's going on permit me to suggest the A.R.R.L. "Antenna Book", 15th Edition, 1988. The foreword is by John Kraus, W8JK; if Kraus thinks it's alright...then it's alright. Don't settle

Replacement. You paid for a working unit. Not your job to sort out their crap. And you have no course of redress if you break your unit. 73 de Andy

The switch is very easy to remove and replace with same or you can do what I and a few others did - replace with surface mount buttons on the front cover (search my posts) Essentially, use a needle

Ugggghhh, don’t mention near-field to me. For me it is the stuff from nightmares. A few times I was called in to investigate communication problems on ships and mobile command centers, where the HF

In combination with FW ch.dfu (edy555_0.1.1.9): I discovered today that with NanoVNA Saver v0.0.10 you may NOT set the LCD of the Nano to TDR. Otherwise, the screens in Saver 10 are not correct. Well,